Symbol Glyco_hydro_68 Pfam clan CL0143 SCOP 1oyg | Pfam PF02435 InterPro IPR003469 SUPERFAMILY 1oyg | |
 | ||
In molecular biology, glycoside hydrolase family 68 is a family of glycoside hydrolases.
Glycoside hydrolases EC 3.2.1. are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families. This classification is available on the CAZy(http://www.cazy.org/GH1.html) web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.
The glycosyl hydrolase 68 family (CAZY GH_68) includes several bacterial levansucrase enzymes, and invertase from Zymomonas. Levansucrase (EC 2.4.1.10), also known as beta-D-fructofuranosyl transferase, catalyses the conversion of sucrose and (2,6-beta-D-fructosyl)(N) to glucose and (2,6-beta-D-fructosyl)(N+1), where other sugars can also act as fructosyl acceptors. Invertase, or extracellular sucrase (EC 3.2.1.26), catalyses the hydrolysis of terminal non-reducing beta-D-fructofuranoside residues in beta-D-fructofuranosides.